#include <iostream>

int main() {
    // 1. 基本变量
    int age = 20;
    double score = 88.5;
    bool passed = true;
    char grade = 'A';

    // 2. 核心运算符
    int future_age = age + 5;        // 加法
    double final_score = score * 0.9; // 乘法
    bool is_adult = (age >= 18);     // 比较
    bool is_qualified = passed && is_adult; // 逻辑与

    // 3. 打印结果
    std::cout << "Age: " << age 
              << "\nFuture Age: " << future_age
              << "\nScore: " << score << " -> " << final_score
              << "\nGrade: " << grade
              << "\nQualified? " << std::boolalpha << is_qualified;

    return 0;
}